我的第一个具有表关联的BookshelfJS / KnexJS脚本存在一些问题。我非常仔细地复制了“一对多”示例，只是将其从“书本”和“页面”切换为“干燥机和汽车”。但是，每当我执行查询并包含withRelated项时，它都不会返回关联的数据（在本例中为汽车），它只会返回驱动程序。
该协会是许多“汽车”的“驾驶员”。我什至在演示中使用KnexJS脚本来创建表，因此它们与示例表几乎相同。继承人的JS脚本：
'use strict';
const Config = require('./config');
const Knex = require( 'knex' )( require('./config').database );
Knex.schema
.createTable('drivers', function(table) {
table.increments('driver_id').primary();
table.string('name');
table.timestamps();
})
.createTable('cars', function(table) {
// using Myisam, since Innodb was throwing an error
table.engine('myisam');
table.increments('car_id').primary();
table.integer('driver_id').references('drivers.driver_id');
table.string('make');
table.string('model');
table.integer('year');
table.timestamps();
})
.then(function(data){
console.log('DONE',data);
})
.catch(function(err){
console.log('ERROR',err);
});
为了获得更多信息，请参见表结构和表内容：
mysql> explain drivers;
+------------+------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+------------------+------+-----+---------+----------------+
| driver_id | int(10) unsigned | NO | PRI | NULL | auto_increment |
| name | varchar(255) | YES | | NULL | |
| created_at | datetime | YES | | NULL | |
| updated_at | datetime | YES | | NULL | |
+------------+------------------+------+-----+---------+----------------+
4 rows in set (0.00 sec)
mysql> explain cars;
+------------+------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+------------------+------+-----+---------+----------------+
| car_id | int(10) unsigned | NO | PRI | NULL | auto_increment |
| driver_id | int(11) | YES | MUL | NULL | |
| make | varchar(255) | YES | | NULL | |
| model | varchar(255) | YES | | NULL | |
| year | int(11) | YES | | NULL | |
| created_at | datetime | YES | | NULL | |
| updated_at | datetime | YES | | NULL | |
+------------+------------------+------+-----+---------+----------------+
7 rows in set (0.00 sec)
mysql> select * from drivers;
+-----------+----------+---------------------+------------+
| driver_id | name | created_at | updated_at |
+-----------+----------+---------------------+------------+
| 1 | John Doe | 2015-12-17 00:00:00 | NULL |
| 2 | The Stig | 2015-12-08 00:00:00 | NULL |
+-----------+----------+---------------------+------------+
2 rows in set (0.00 sec)
mysql> select * from cars;
+--------+-----------+-----------+--------+------+---------------------+------------+
| car_id | driver_id | make | model | year | created_at | updated_at |
+--------+-----------+-----------+--------+------+---------------------+------------+
| 1 | 1 | Chevrolet | Camaro | 2014 | 2015-12-18 00:00:00 | NULL |
| 2 | 1 | Acura | RSX-S | 2004 | 2015-12-11 00:00:00 | NULL |
| 3 | 2 | Ford | Focus | 2004 | 2015-12-18 00:00:00 | NULL |
| 4 | 2 | Nissan | Maxima | 2001 | 2015-12-17 00:00:00 | NULL |
| 5 | 2 | Geo | Metro | 1998 | 2015-12-18 00:00:00 | NULL |
+--------+-----------+-----------+--------+------+---------------------+------------+
5 rows in set (0.00 sec)
然后是带有模型和查询执行的实际NodeJS脚本：
// app.js
'use strict';
const Config = require('./config');
const Bookshelf = require('./bookshelf');
var Driver = Bookshelf.Model.extend({
tableName: 'drivers',
cars: function() {
return this.hasMany(Car);
}
});
var Car = Bookshelf.Model.extend({
tableName: 'cars',
driver: function() {
return this.belongsTo( Driver );
}
});
new Driver()
.where({
driver_id: 2
})
.fetch({
withRelated: ['cars']
})
.then(function(driver) {
console.log('RELATED CAR:', JSON.stringify(driver));
console.log('DRIVER DATA', driver);
});
此外，以下是bookshelf.js文件，其中包含KnexJS和BookshelfJS连接：
// bookshelf.js
'use strict';
var knex = require( 'knex' )( require('./config').database );
module.exports = require('bookshelf')( knex );
这是执行app.js时的控制台输出
RELATED CAR: {"driver_id":2,"name":"The Stig","created_at":"2015-12-08T07:00:00.000Z","updated_at":null,"cars":[]}
DRIVER DATA ModelBase {
attributes:
{ driver_id: 2,
name: 'The Stig',
created_at: Tue Dec 08 2015 00:00:00 GMT-0700 (MST),
updated_at: null },
_previousAttributes:
{ driver_id: 2,
name: 'The Stig',
created_at: Tue Dec 08 2015 00:00:00 GMT-0700 (MST),
updated_at: null },
changed: {},
relations:
{ cars:
CollectionBase {
model: [Object],
length: 0,
models: [],
_byId: {},
relatedData: [Object] } },
cid: 'c1',
_knex: null }
我不确定问题出在什么地方，我觉得它有些简单，但我却忽略了。
谢谢！
最佳答案
有两个问题cars.driver_id需要取消签名，就像在drivers表中引用的ID列一样
我将表索引列创建为${singular_table_name}_id，根据我的经验，这是最常用的方法，但是BookshelfJS希望它只是id。因此，我可以将ID列名称更改为id，或将idAttribute值设置为${singular_table_name}_id
上述更改后，一切正常。
关于javascript - 使用BookshelfJS/KnexJS在NodeJS脚本中进行基本表关联，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/34426392/